Various methods have been employed to obtain high burning rate propellants. One method of obtaining very high burning rates from propellants has been through the use of aluminum staples. The use of staple, however, complicates the processing of the propellant because special casting techinques are necessary to avoid orientation of the fibers along flow lines. The more recent use of liquid burning rate catalysts (particularly of the organoiron or carborane types) has resulted in problems associated with the use of such catalysts, such as, their relatively high volatility, their high freezing points, and their tendencies to migrate within the propellant and into the liner and insulation of the rocket motor. In order to overcome these migratory tendencies, it has been necessary to incorporate high percentages of burning rate promoter into the insulation to produce a near-equilibrium situation insofar as catalyst migration is concerned, thus further complicating the manufacture of these types of solid rocket motors.
Well known in the solid propellant rocket motor art is the manufacture of resonance rods and their use in solid propellant rocket motor to eliminate combustion instability. Such resonance rods are usually fabricated from asbestos-reinforced phenolic resin. The function of resonance rods is the suppression of combustion instability.
Advantageous would be resonance rods which serve a dual purpose.
Therefore, an object of this invention is to provide resonance rod which serve a dual purpose (e.g., suppression of combustion instability and catalyzing the burning of the solid propellant).
Another object of this invention is to provide resonance rods of the ablative type formulation which contain a burning rate promoter as part of the formulation.
Still another object of this invention is to provide porous resonance rods infiltrated with additives which suppress combustion instabilities and which serve to promote burning rate of propellants.